The invention relates to a transfer machine intented for transferring loads, especially containers. Hereinbelow, the term load can also be used to refer both to the load and to the container. The transfer machine comprises:
a frame equipped with a wheelwork,
a horizontal support plane in connection with the frame for supporting the load during transfer,
a vertical transfer apparatus for lifting the load on and off the support of the support plane, wherein
the vertical transfer apparatus is arranged to lift and lower loads from the side of the transfer machine and thereby from the side of the support plane.
A side reach type transfer machine of the above kind is disclosed for example in publication WO 97/26150. It is, however, difficult to implement the construction of the solution known from this publication especially because loads are arranged to be lifted in such a way that the stresses caused by the vertical transfer machine and by the load to be lifted or lowered are confined entirely to one side of the transfer machine at least at the stages of starting completing the transfers, wherein it is extremely difficult to balance the transfer machine.
The purpose of the present invention is to eliminate the aforementioned problems and to improve the state of art in the field. To attain these purposes, the transfer machine according to the invention is primarily characterized in that
the vertical transfer apparatus is placed in connection with the frame at the first side of the support plane, and that
the vertical transfer apparatus is arranged to reach over the support plane in order to move the load onto or off the support plane from the second side of the support plane.
The primary advantage of the above-presented solution is that when the load is lifted up or lowered down, all the heavy components and structures of the vertical transfer apparatus are located on the opposite side of the transfer machine with respect to the load. Thus, separate counterbalance weights are not required, and the construction balances the stresses caused by the load. When placed at the side of the support plane, the vertical transfer apparatus can be arranged in a considerably low position, which significantly lowers the centre of gravity in the transfer machine.
Furthermore, according to a preferred embodiment, the vertical transfer apparatus is supported to the axle group of the wheelwork. In this solution, loads not exceeding 30 tons, in weight can be lifted and lowered by means of the vertical transfer apparatus in such a way that the transfer machine is supported by the wheelwork. With heavier loads, especially those of 40 to 50 tons in weight, it is possible to use stabilizers, wherein the stress on the wheelwork remains at a moderate level.
Moreover, according to a preferred embodiment, grippers, or the like, which are arranged to grip the load, are adjustable in their position with respect to the longitudinal direction of the transfer machine, especially with the purpose of balancing the stress on the wheelwork and/or on the stabilizers. With this solution, the advantage is achieved that the stresses on the wheels and stabilizers of the transfer machine can be distributed evenly in an optimal manner when lifting and lowering the load, wherein it is possible to lift and lower the load safely.
The aforementioned arrangements for balancing the stress also increase the operating range of the machine for it is possible to provide the transfer machine with a considerably long vertical transfer apparatus. Thus, it is possible to manipulate for example several superimposed loads simultaneously or to collect a number of loads on top of each other.
With the structural solutions according to, the invention it is possible to produce a transfer machine which is suitable for use in a variety of locations and situations in an adaptable manner, thanks to the low centre of gravity, the considerably small dimensions especially with respect to the capacity, and the fact that load is manipulated from its side and transferred in its longitudinal direction.
The other dependent claims present some preferred embodiments of the transfer machine according to the invention.